Question

Simplify using law(s) of exponents: $\sqrt{98}$

• A. $7\sqrt{3}$
• B. $7$
• C. $7\sqrt{2}$
• D. $6\sqrt{2}$

Answer 1

The correct option is C

$7\sqrt{2}$

$\sqrt{98}$
$=(98{)}^{\frac{1}{2}}$
$=(2\times 49{)}^{\frac{1}{2}}$
$=2^{\frac{1}{2}}\times {49}^{\frac{1}{2}}$ $[\because (ab{)}^n=a^n\times b^n]$
$=2^{\frac{1}{2}}\times 7$
$=7\sqrt{2}$